The most important thing before purchasing this booster is to contact us ( sales@tdmaxonline.com ) to make sure your signal frequency in your address if you are not 100% sure it is 850MHz. Many buyers bought wrong items which do not work because they did not make sure their signal frequency. (Note: Please do not just consult your carrier about your signal frequency you will be easily misled by their hotline operators. Please spend several minutes to contact us it won't be complicated.)</br>Works with all 2G 3G 4G 850mhz networks (Band 5 UL: 824-849MHz DL: 869-894MHz) in US Canada and Mexico.</br>ALC function enables to lower the output gain to preset max. level automatically while the outdoor signal is too strong. And it can work well with all 2G 3G and 4G 850MHz (Band 5) data and voice service for 4G LTE FDD 850MHz (Band 5) networks this kit only works with voice service please do not expect this item can work with your 4G data service.</br>When the input of this booster is good (outdoor signal is good) the max. indoor signal coverage of this booster kit is about 1000 sq. ft in open space. If your outdoor signal is poor the actual indoor coverage will be smaller accordingly. If you expect excellent indoor performance while your outdoor signal is very poor?? or your house is very big and you want your whole big house has good signal receiption?? you must choose bigger and more powerful booster kit with more indoor antennas.</br>All carriers run their services on multiple frequencies?? for example running your 3G UMTS service on 850mhz and 1900mhz?? but if your house is only within your carrier's 1900MHz coverage?? 850MHz signal is not available there?? this 850MHz booster is wrong to you! So please do not purchase 850MHz booster simply because your carrier has 850MHz network?? you need to check with us seriously.</br></br>Product Description</br></br><b>Friendly Reminder: Please contact me to make sure your signal frequency if you are not 100% sure about your signal frequency is 850MHz?? otherwise?? this kit might not work for you. Please note that even if your neighbor or friend has working 850MHz signal booster?? it